1. Field of the Invention
This invention relates to an improved apparatus for moving a conveyor feeder means used to propel anode rods through rodding room machinery. More particularly, the invention relates to an improved apparatus wherein the short stroke of a fluid-powered piston is amplified by cables and pulleys to move a feeder mechanism.
2. Description of the Prior Art
Spent anodes that are removed from operating electrolytic cells are returned to a carbon plant to be refurbished for reuse in the cells. These spent anodes are attached to the trolleys of a power-and-free conveyor system at the entrance to the rodding room and remain so for the duration of their trip through the room.
Power-and-free conveyor systems incorporate a constantly moving power chain operating above the trolleys. Typically, the power chain has protruding lugs spaced at uniform (and frequent) intervals along its entire length. The trolleys have vertically sliding rods that, when extended, are in the path of the lugs on the power chain. When the power chain lugs contact the extended trolley rods (commonly referred to as "dogs"), the trolleys are moved along the conveyor at the speed of the power chain.
Trolleys are stopped and started frequently during their trip through the rodding room, as it is necessary for the trolleys to remain briefly at each of several work stations. Trolley stops are accomplished by locally increasing the elevation of the power chain so that the lugs disengage the trolley dogs. (There is linkage on each trolley dog that will depress it out of engagement with the power chain if the trolley runs into the rear of a preceding stopped trolley. Consequently, when one trolley is stopped, those following also stop.) Chain-driven trolley motion resumes when the trolley is advanced into a section of conveyor where the power chain has been rerouted down to its original elevation, or when a preceding trolley resumes motion. Thus the "power-and-free" appellation.
Feeders are then necessary to move the trolleys into the various work stations, then back into engagement with the power chain after completion of each operation. The apparatus of the present invention provides the motive force for such feeders.
Conventionally, feed mechanisms for rodding room machinery are mounted on a frame above each machine and are moved by a piston coupled to a long-stroke pneumatic cylinder as depicted diagrammatically in FIG. 1. The piston may be required to move as much as 80 inches or more, thus requiring a large-diameter cylinder, e.g., four inches or more.
A short-stroke, high-powered hydraulic cylinder instead of the long-stroke pneumatic cylinder is desirable if means to amplify the motion of the short-stroke cylinder is made available.